Remote Sensing Methods Outline

  • Landsat-5 imagery provided by instructors (determine source from instructors)
  • Use ERDAS Imagine 2010 to perform image analysis
    • Unsupervised image processing utility was used to classify image into 12 classes
    • These 12 classes were categorized one-by-one
      1. Water
      2. Roads
      3. Forest / Woods
      4. Forest / Forest
      5. Forest / Open Land
      6. Townhouse / Apartment
      7. Single Family Residential
      8. Low Density Residential
      9. Commercial
      10. Commercial / Rooftops
      11. Office / Light Industrial
      12. Agricultural
    • Google Earth was used to assist in identifying the major feature being classified
  • Classified Landsat-5 image was loaded into ESRI's Arcmap 10.1 to obtain percentage of classes
    • The overall site image was clipped using the watershed boundaries for Marsh & Long Island Creek
      • 2 separate images were created; one for each watershed
    • The 12 classes were further reduced to 9 classes
      1. Water
      2. Forest
      3. Agriculture
      4. Roads
      5. Single Family Residential
      6. Low Density Residential
      7. Townhouse / Apartment
      8. Office / Light Industrial
      9. Commercial
    • Using the clipped, classified image, the total number of pixels were determined
    • The sum of each category's pixel count was determined
    • Percentages were calculated into the attribute table of the image by using the following formula:
      • PERCENTAGE = (([Classified Pixel Count] / [Total Pixel Count])*100) * [Landuse Coefficient]
    • This process was performed for each year of Landsat5 imagery.